Various configuration for vacuum cleaner heads are known in the art. Vacuum cleaner heads may be used in conjunction with upright vacuum cleaners. In such a case, a vacuum cleaner head may include a motor for creating an air flow through the vacuum cleaner. In such a case, the vacuum cleaner may also be connected to an electric motor to drive a rotatably mounted brush. Alternately, a turbine driven rotatably mounted brush may be provided in the vacuum cleaner head. Similarly, in the case of canister vacuum cleaners and central vacuum cleaning systems, a rotatably mounted brush which is driven either by an electric motor or a turbine is known in the industry.
If a turbine is placed in the air flow path, it may become clogged (such as by hairs or other elongate particulate material) which may be entrained in the dirty air stream entering the vacuum cleaner head. Accordingly, it is well known in the industry to mount the turbine so as to be operated by clean air which enters the vacuum cleaner head such as through the top of the vacuum cleaner head. One disadvantage with this approach is that not all of the air which enters the vacuum cleaner head enters through the dirty air inlet. Accordingly, a portion of the suction created by the motor is used to operate the turbine and is not available for use in entraining dirt.
While it is known to locate a turbine in the dirty air flow path through the vacuum cleaner head, suitable means for preventing the clogging of the turbine have not been developed.